As has been pointed out, all this analysis shows is if the oil is still servicable. How is that useful?

Should I do this analysis everytime I think I am approaching the time to change my oil, spend the $35 and go...'oh, oils still good, I'll wait another few thousand miles...'

Should I do the analysis waiting for a result that shows my oil is no longer servicable and then change the oil?

Should I do the analysis and get a more exact milage for when I should change the oil even though the conditions that these results are based on are varibles that can change greatly and the closer I am to an exact milage, the more likely I am to exceed the oil life servicability?

OP, how has the info you have attained from spending $35 affected how often you change your oil? How do you think your driving for XX miles between oil changes differs so greatly from anyone else and requires a specialized oil change interval? Yes, you have shown that 7500 miles is way to soon to be changing oil on a plan, but I think everyone already realizes that and choose to do it anyway.

The oil company list how long their oils are good for. BMW list how often you should change your oil. I bet either one is a safe bet (using BMW's oil list), especially BMW's and all their testing has already been done, is more accurate, useful and cost me nothing. What does BMW call for? 15k miles? Hell, oil will probably be good till 20k....maybe. Won't be me pushing that limit though. I change mine at 10k ish. I pulled that number out of my ass and then spent $35 on Alaskan Amber. Perhaps I could have gone all the way to 15k and beyond, but I am not that concerned about wringing every last bit of usefulness out of the oil and filter. 10k miles is many months for me. No UOA is going to give me a good indication that my driving for 10k miles will cause the same wear for the next 10k miles. Their info is useless.

You know when a UOA is useful? When your engine is running way too hot, blows apart, catastrophically fails. Then you can do a UOA to point the finger at the oil as the cause or eliminate it or get an idea what was going on in the motor.

As has been pointed out, all this analysis shows is if the oil is still servicable. How is that useful?

Should I do this analysis everytime I think I am approaching the time to change my oil, spend the $35 and go...'oh, oils still good, I'll wait another few thousand miles...'

Should I do the analysis waiting for a result that shows my oil is no longer servicable and then change the oil?

Should I do the analysis and get a more exact milage for when I should change the oil even though the conditions that these results are based on are varibles that can change greatly and the closer I am to an exact milage, the more likely I am to exceed the oil life servicability?

OP, how has the info you have attained from spending $35 affected how often you change your oil? How do you think your driving for XX miles between oil changes differs so greatly from anyone else and requires a specialized oil change interval? Yes, you have shown that 7500 miles is way to soon to be changing oil on a plan, but I think everyone already realizes that and choose to do it anyway.

The oil company list how long their oils are good for. BMW list how often you should change your oil. I bet either one is a safe bet (using BMW's oil list), especially BMW's and all their testing has already been done, is more accurate, useful and cost me nothing. What does BMW call for? 15k miles? Hell, oil will probably be good till 20k....maybe. Won't be me pushing that limit though. I change mine at 10k ish. I pulled that number out of my ass and then spent $35 on Alaskan Amber. Perhaps I could have gone all the way to 15k and beyond, but I am not that concerned about wringing every last bit of usefulness out of the oil and filter. 10k miles is many months for me. No UOA is going to give me a good indication that my driving for 10k miles will cause the same wear for the next 10k miles. Their info is useless.

You know when a UOA is useful? When your engine is running way too hot, blows apart, catastrophically fails. Then you can do a UOA to point the finger at the oil as the cause or eliminate it or get an idea what was going on in the motor.

Hmm, it feels kinda strange, and I'm not sure how to explain. It's like you guys are responding to a DIFFERENT thread, as opposed to MY thread.

You guys are obviously against UOAs and are passionate enough to take a stance in communicating your point of view. I respect that.

But, I'm not sure why you guys keep responding as if this is a generic UOA thread? The first response is understandable, and I enjoyed reading it, but now it's getting strange.

I've clearly stated that I track my car, and am concerned about my engine. The UOA, while not comprehensive, allows me to get a snapshot of the trace elements of a certain size (once again, not saying it detects all particles...I hate putting in all these disclaimers cuz of how this thread is going). It is very valuable to me to know that my engine is wearing well within the limitations of what a UOA can inform me. I mean, I was HONESTLY expectating Iron, Copper, etc. to be in the hundreds of ppm due to the stress of track days. I wanted some data to confirm or dispel my fears! Imagine how happy I was to receive this report showing I'm actually wearing better than average.

In regards to the TBN analysis, yes, I was doing 7.5K oil change intervals (6.8K), and you're right, sometimes I thought it was aggressive and early when I'm not doing track days. So I felt it was valuable to spend $35 to dial-in my oil change interval for my driving style. I'm now comfortable with extending it to 10K miles, whereas if I did it without an UOA, there would always be a what-if at the back of my head....it's peace of mind, you know?

Ok, hope you understand my point of view. It really feels strange because here I am acknowledging yours, but it's like you guys are choosing to ignore the reason I did a UOA, and just using this thread to go on a spiel against UOAs in general.

Rather, why not just think of it as cool, 'another member actively contributing to the e90post community'?

Yes, you have shown that 7500 miles is way to soon to be changing oil on a plan, but I think everyone already realizes that and choose to do it anyway.

The oil company list how long their oils are good for. BMW list how often you should change your oil. I bet either one is a safe bet (using BMW's oil list), especially BMW's and all their testing has already been done, is more accurate, useful and cost me nothing.

Does everyone really already realize that? Whenever there is a thread about oil change intervals, you almost always see people claiming that the 15,000 mile BMW interval was developed by a bunch of greedy corporate accountants, rather than engineers. These same people usually point out the unlikely coincidence of BMW recommending longer intervals for maintenance items at the same time that they start paying offering "free" maintenance. It's probably one of the most hotly debated topics on here. So, when somebody offers actual, objective data I think that's a good thing. Too many people post anecdotal evidence of how they've been doing such and such practice for such and such number of miles and haven't had any issues, therefore they are correct. As an engineer, I prefer hard numbers.

It's true that BMW and the oil companies have recommended intervals, but it's not always clear where those intervals come from. What are their test conditions and assumptions? Are they based on a casual Camry driver, or a lead footed enthusiast with a high performance engine? Somewhere in the middle I assume, but we don't know exactly where the line is. In the OP's case, he "beats on" his car more than most everyday drivers, and he chose to spend a minimal fee to get a rough look at how his oil was holding up. Nothing wrong with that, and I'd say it's a better strategy than pulling a random interval out of thin air, simply because it's a round number. Now don't get me wrong, I'm not hear to judge your maintenance practices. On the contrary, my point is that I disagree with everyone who's judging the OP's decision to "waste" a lousy 35 bucks to get some real data and be better informed.

Obviously the analysis here has limitations, but some data is better than none in my mind.

In any case, you made some good points, thanks for that.

Quote:

Originally Posted by ENINTY

Exactly! Thanks for typing all of that, as I was too lazy to. Thanks.

Ok, we get it. You don't see the value in a UOA. FYI, you don't have to keep posting here. Just ignore it and let those of us who found the results useful to ourselves. Otherwise you're not contributing anything useful to the thread.

Does everyone really already realize that? Whenever there is a thread about oil change intervals, you almost always see people claiming that the 15,000 mile BMW interval was developed by a bunch of greedy corporate accountants, rather than engineers. These same people usually point out the unlikely coincidence of BMW recommending longer intervals for maintenance items at the same time that they start paying offering "free" maintenance. It's probably one of the most hotly debated topics on here. So, when somebody offers actual, objective data I think that's a good thing. Too many people post anecdotal evidence of how they've been doing such and such practice for such and such number of miles and haven't had any issues, therefore they are correct. As an engineer, I prefer hard numbers.

It's true that BMW and the oil companies have recommended intervals, but it's not always clear where those intervals come from. What are their test conditions and assumptions? Are they based on a casual Camry driver, or a lead footed enthusiast with a high performance engine? Somewhere in the middle I assume, but we don't know exactly where the line is. In the OP's case, he "beats on" his car more than most everyday drivers, and he chose to spend a minimal fee to get a rough look at how his oil was holding up. Nothing wrong with that, and I'd say it's a better strategy than pulling a random interval out of thin air, simply because it's a round number. Now don't get me wrong, I'm not hear to judge your maintenance practices. On the contrary, my point is that I disagree with everyone who's judging the OP's decision to "waste" a lousy 35 bucks to get some real data and be better informed.

Obviously the analysis here has limitations, but some data is better than none in my mind.

In any case, you made some good points, thanks for that.

Ok, we get it. You don't see the value in a UOA. FYI, you don't have to keep posting here. Just ignore it and let those of us who found the results useful to ourselves. Otherwise you're not contributing anything useful to the thread.

And what do the hard numbers tell the OP? That his engine will last 10,000, 20,000 miles longer than if he followed a 15,000 mile OCI? The OP beats on his car because he tracks it 2 days a month? How many miles is that? It is really all that hard on the engine? So he's decided to change the oil every 10,000 miles instead of 7,500 and how long will the OP keep his car anyway? If the engine fails at 220,000 miles instead of 260,000 miles is he going to have the car that long? I doubt it based on they way he treats his car now. The car is a toy to him, which he hopes will put up with the abuse so it can double as a daily driver. All the while the suspension, cooling system, transmission, differential, wheel bearings, and chassis will have shortened lives as well. But he's trying to save money on maintenance costs by extending the OCI by 2,500 miles; sorry it just doesn't make sense to me.

One of the purposes of this forum is to debate issues, I'm debating. You just don't like my argument because it is a good one, so your answer is "just shut up."

It's true that BMW and the oil companies have recommended intervals, but it's not always clear where those intervals come from. What are their test conditions and assumptions? Are they based on a casual Camry driver, or a lead footed enthusiast with a high performance engine? Somewhere in the middle I assume, but we don't know exactly where the line is.
In any case, you made some good points, thanks for that.

The engine bench tests are a compilation from various members of the ACEA (All major OEM's are members). Then each OEM has their own specific bench tests and requirements (EX, VW(AUDI) 507.00 will always be a 30 weight oil). Coincedentially(sp?) longer service intervals didn't start coming out until the ACEA developed the standards for extended drains. IIRC this is about the same time you started to see LL98 and BMW paid maintenance. So you're comments about people having a lack of factual evidence supporting BMW short changing maintenance has some credence. Almost every OEM now has some sort of oil life monitor for extended drains.

The engine bench tests are a compilation from various members of the ACEA (All major OEM's are members). Then each OEM has their own specific bench tests and requirements (EX, VW(AUDI) 507.00 will always be a 30 weight oil). Coincedentially(sp?) longer service intervals didn't start coming out until the ACEA developed the standards for extended drains. IIRC this is about the same time you started to see LL98 and BMW paid maintenance. So you're comments about people having a lack of factual evidence supporting BMW short changing maintenance has some credence. Almost every OEM now has some sort of oil life monitor for extended drains.

So I'd like to add some information on this too. My 1st new-purchase BMW was a 1989 E30 325i in november 1988, which had an oil life monitor system in it, and based on the type of driving my wife did (it was primarily her car) the CBS called for oil changes about every 9,000 - 12,000 miles. In January 1997 we bought a Z3 just about the time BMW had started the "free" maintenance program. At that time in 1997 the maintenance schedule for the Z3 was basically the same as the E30 (what people now refer to as the "old-school schedule"). So for the 1997 model year BMW did the trans and diff oil service at 30,000 miles on the Z3, and the coolant change at 2 years. The OCI for the Z3 is around 9,000 miles so it is just about the same as the E30. If BMW was trying to skimp out on maintenance because they are now paying for it they would have drastically changed the maintenance schedule in 1997. Free maintenance is a misnomer anyway, as they just wrap the cost into the price of the vehicle, so if BMW wanted to keep the old-school schedule for current model years they would just include the cost of the old school maintenance program into the new vehicle price.

IMO BMW started the new-school maintenance schedule as a “free” service so as to support their burgeoning Lease/CPO business, where they could show potential customers of CPO cars that the early maintenance up to 40,000 miles was done by BMW. A suspecting CPO customer would be leery of a used, previously leased car, because the original leasor could just skimp on the maintenance and no one would have been the wiser.

So I'd like to add some information on this too. My 1st new-purchase BMW was a 1989 E30 325i in november 1988, which had an oil life monitor system in it, and based on the type of driving my wife did (it was primarily her car) the CBS called for oil changes about every 9,000 - 12,000 miles. In January 1997 we bought a Z3 just about the time BMW had started the "free" maintenance program. At that time in 1997 the maintenance schedule for the Z3 was basically the same as the E30 (what people now refer to as the "old-school schedule"). So for the 1997 model year BMW did the trans and diff oil service at 30,000 miles on the Z3, and the coolant change at 2 years. The OCI for the Z3 is around 9,000 miles so it is just about the same as the E30. If BMW was trying to skimp out on maintenance because they are now paying for it they would have drastically changed the maintenance schedule in 1997. Free maintenance is a misnomer anyway, as they just wrap the cost into the price of the vehicle, so if BMW wanted to keep the old-school schedule for current model years they would just include the cost of the old school maintenance program into the new vehicle price.

IMO BMW started the new-school maintenance schedule as a “free” service so as to support their burgeoning Lease/CPO business, where they could show potential customers of CPO cars that the early maintenance up to 40,000 miles was done by BMW. A suspecting CPO customer would be leery of a used, previously leased car, because the original leasor could just skimp on the maintenance and no one would have been the wiser.

Didn't BMW do away with the 1,200 mile break-in service for all non-M vehicles when they rolled out the "free" maintenance? As you know the differential/trans service went away with the new (3,5,7 series cars in the late 1990s). It was all lifetime and later revised to mean 100k mile. Now naysayers and people who've been involved with the brand since the 70's will say that BMW did it to save $$ on "free" maintenance, because these newer parts aren't any more reliable than the ones which came before it.